Drill



i Feb. 2l, 1928 R- E- OVERMAN DRILL Filed 001?. 16. 1925 gmk www.,

Patented Feb. 21, 1928.

PATENT oFF1cE.'

BOSCOE E. OVEBMAN, OF VAN NUYS, CALIFORNIA..

DRILL.'

Application led October 16, 1928. Seria! No. 888.798.

This invention relates to a rotary drill and more particularly it relates to the formatlon, configuration of, and positioning, and fastening means for, the actual drilling members of a drill and is an improvement on a rotary drill'described and claimed in Patent #1,468,509 granted to me September 18, 1923.

An object of this invention is to provide a rotary improved conguration and position.

Another object of this invention is to provide improved means for detachably securing certain of said drilling members to their supporting parts.

Another object of this invention is to provide cutting members of a rotary drill which necessitate less lubrication than those previousl em loyed.

A furt ier o ject of this invention is the provision of more durable drilling members.

A still further object of this invention is to provide a rotary drill with tools which are l renewable and interchangeable and which may be readily removed.

Another object is to provide a well-drill- Y ing tool of the rotary type embodying a series of revolvable elements on the tip thereof, so constructed and arran edY as to effect a drilling action by the crus ing and comminuting of the materials worked upon so that the materials may be 'readily discharged in water.

Another object is to provide a well-drilling tool of the rotary type with crushing and grinding rollers so arranged relative to each other and to the vertical axis of rotation of the drill that Athe material acted on thereby will not be only finely ground but also thoroughly admixed with water so that the water and the solids may be readily re-l moved.

Another object is to provide a tool of the above character which is so constructed as to insure drilling of a straight hole, which is rapid in operation,and adapted for use in various earth formations.

' A further object is to provide a tool with an arrangement of bearing rollersxwhereb an undercutting act-ion` may be readily e ected, for the urpose of allowing the casing to follow t e tool during the operation drill having drilling members of of the drillin and embodying means whereby the too may be expanded and con tracted.

Other objects will appear hereinafter.

The invention is illustrated in the accompanying drawings, in which- Fig. 1 is a view showing a well casing in section, with a portion of the tool disposed therein in contracted position. l.

Fig. 2 is a view in elevation of the tool in its expanded position.

lig. 3 is a view in side elevation of the too Fig. 4 is an end view taken on the line L14 of Fig. 2, showing the arrangement of the boring rolls.

Fig. 5 is a central longitudinal section of a complementary crushing roller taken on the line 5-5 of Fig. 3, and showing a method of securing the roller to a portion of the tool.

Fig. 6 is a view in transverse section as seen on the line 6-6 of Fig. 2.

More specifically, in Fig. 1, 5 indicates the shank of the tool, the lower portion of which is wedge-shape in form to provide inclined or tapered side walls. 6 on opposingl sides thereof, the end walls 7 of the shank being straight and parallel. The upper portion of the shank converges into a square stem 8 fitted with an annular flan e 9 formin the upper end of the shank an on which ange is formed a tapered threaded ortion 10 (shown in Fig. 2) adapted to screwed into the lower end of a tubular drill rod 11 adapted to engage dove-tail grooves formed on the inner inclined faces of a pair of slips 14, which are designed to be slidably mount- :ed on the inclined faces 6 of the shank. The

sides of the slips 14 are preferably ush with the flat end faces o the shank, as shown in Fig. 4, so that the slips and the .extend longitudinally of the shank and are shank will have a corresponding width. Formed on the sides of the slips 14 arel vertically extending channels 15 into which the ends of across bar 16 project, a cross bar 16 being mounted on each flat end face 7 of the shank and countersunk therein. These cross bars are designed to limit the longitudinal movement .of the slips and shank relative to each other and are adapted to engage the upper ends of the channels 15 as shown in Fig. 1, or to abut against the lower ends of the channel, as shown in Fig. 2, according to whether the surface is contracted or expanded relative to each other on the shank, as will be described later.

Mounted on the lower end of the shank 5 is a series of case hardened corrugated rollers 17 of uniform diameter rotatably mounted on a shaft 19 supported in projections 20 onthe end of the shank. The projections 20 comprise demountable plates which are countersunk in the faces 7 of the shank 5 and are secured thereto by screws 20. Mountedon the end of each slip 14 with its largest diameter outermost is a case-hardened tapered corrugated roller 21 which is designed to rotate on a shaft 22 as shown in Fig. 5. The shaft 22 is carried at one end by a projection 23 on the lower outer ortion of the slip 14 and at its inner end y an angular plate 24 having a square aperture 25 therein 1n which a squared end portion 25 on the shaft 22 extends. The plate 24 is detachably alixed to the inner side of the slip 14, the dove tail rib 13 being cut to accommodate the plate. The shaft 22 is positioned in its bearingat such angle that the bottom line A ofthe tapered roller 21 is at right angles to the axis of the drill and therefore at right angles to the direction of drilling. The rollers 17 and 21 are formed with peripheral ribs and grooves so as to adapt the rollers to have simultaneously a crushing` and a griding action during the rotation of the dri f As aimeans for affording a substantial mounting for the outer ends of the shafts 22, the projections 23 are provided with inwardly extending nuts or collars 26 the round heads of which project into recesses' 27 in the outerends of the rollers 21, so that the rollers will extend close to the edges of the slips, and the shaft bearings will not project materially beyond the outer faces thereof, this construction providing wide bearings for the shaft. The nuts or collars 2 6 are lnternally threaded, their headed portions rest upon the inner face of the projection 23, andthe shafts 22 are screwed into enga ement therewith to ermit ready remova and re lacement o the shafts and rollers. The s aft 19 is mounted in a manner similar to .that of the shafts 22, one end thereof being screwed into a collar 26 carrled by a projection 20 which collar extends 21 bearing on the bottom of the well, these rollers will both rotate 'and slide in traversing the surface to effect a crushing and grinding action thereon. The rollers 21 are arranged so that a portion of their enlarged outer ends will project diagonally beyond the outer faces of the slips so that during rotation of the drill they will cut a diameter greater than that of the combined slips and Shanks and thereby afford clearance between the walls of the bore and the slips. This bore is cut under the lower end of the casing to permit the latter being lowered therein.

In the operation of the invention, the slips are advanced on the shank so that they will extend beyond the lower end thereof, in which position they will be contracted relative to each other by reason of the inclination or taper of their slide mounting. When thus disposed the slips will be supported on the cross bars 16. The drill may then be raised or lowered through the well casing 30, as shown in Fig. 1. When the slips come to rest on the bottom of the bore the shank may be lowered between the sli s and by reason of its wedge shape cause t e slips to move outwardly into their expanded position below the lower end of the casing. When the shank is in its lowermost position between the slips, the cross bar 16 will abut against the lower ends of the channels l5 so that the shank of the drill and the load imposed thereon will bear upon the slips. The shank and slips are so proportioned that when the shank is in its lowermost osition between the slips, the several ro 1ers will be positioned on the same plane.

During rotation of the drill, half of the series of rollers 17 will rotate on their shaft in an opposite direction to the other half and-by extending diametrially across the axis of rotation of the drill will form the central portion of the bore. The rollers 21 being arranged with their outer ends disposed beyond the path of travel of the outer izo ends of the inner rollers 17 will act to form A water from the bore.

It will be noted that according to my construction the rollers 'do not roll free, but slide and roll and that my peculiar construction provides a device which minimizes the wear between the roller and the shaft, a

condition which calls for a relatively small amount of lubrication. My construction also provides a device in whlch the bits are given lengthened life. Another valuable eiect of m improved drill is that during action it e ects simultaneously a crushing and a shearing action and thereby brings about an easily removable admixture of the dbris with the water introduced into the drill, which may be readily removed from the well. This effect is in strikin contrast to previous drills wherein the rol ers rolled but did not slide over the lsurface to be cuti 26 an action which tended to pack the materia cut, and thus tending to prevent its mixture with the water intended to wash away the dbris.

I claim- In a rotary drill, a slip having an integral tapering end projection on its outer ower end portion, a. nut screwed into the inner face of said rojection, said nut having a round head a apted to form a bearing surface and being mternally threaded, a shaft having one of its ends screwed into -said nut to be operatively,non-rotatable, a

rotatable corrugated drilhng roller supported by said shaft and having a portion of its bearing upon the head of said nut, the axisv of rotation of said roller being in such a direction as to tend in operatlon to force said roller toward the outer face of said slip and a support for the other end of said s a t.

RoscoE E. OVERMAN. 

